Economics of Selected Water Control Technologies and their Successful Use: The Case of Ethiopia

Using a production function, marginal productivity of farm inputs and benefit-cost analysis, we explore the economics of selected water control technologies. From the production function, all farm inputs, including irrigation water is found to have a significant and positive effect on yield. Marginal value products of farm inputs are found to be positive but their magnitudes differ by type of control structures, crop type, agro-ecology and regions. The net present values of all water control structures are positive. There is a favorable precondition for sustainable adoption of these controls technologies and institutionalizing some sort of cost recovery schemes. The level of education, the ratio of irrigated land allocated to irrigated annuals and perennials, access to markets and off-farm income are found to have significant effect on successful use of these control structures. Recommendations and policy implications are drawn accordingly.

本研究采用生产函数（production function）、农业投入边际生产率（marginal productivity）分析及成本效益分析（benefit-cost analysis）方法，探讨了选定控水技术（water control technologies）的经济学特性。通过生产函数分析发现，包括灌溉用水在内的所有农业投入均对产量产生显著正向影响。农业投入的边际价值产品（marginal value products）均为正值，但其数值大小因控水设施类型、作物种类、农业生态条件及区域而异。所有控水设施的净现值（net present values）均为正值。这些控水技术的可持续采用以及某种成本回收机制（cost recovery schemes）的制度化具备有利前提条件。教育水平、分配给灌溉一年生及多年生作物的灌溉土地比例、市场可达性以及非农收入，均对这些控水设施的成功使用产生显著影响。据此提出了相关建议及政策启示。